沈亞強(qiáng) 姚祥坦 程旺大

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藕–魚種養(yǎng)結(jié)合模式對(duì)藕田底棲動(dòng)物的影響*

沈亞強(qiáng) 姚祥坦 程旺大**

(浙江省嘉興市農(nóng)業(yè)科學(xué)研究院(所) 嘉興 314016)

低洼田因地制宜創(chuàng)新農(nóng)作制度, 構(gòu)建的藕-魚種養(yǎng)結(jié)合模式是一種新型高效的生態(tài)農(nóng)業(yè)模式, 其中底棲動(dòng)物是這個(gè)復(fù)合生態(tài)系統(tǒng)的重要組成部分。為研究藕-魚種養(yǎng)結(jié)合模式對(duì)藕田底棲動(dòng)物的影響, 本試驗(yàn)設(shè)計(jì)了3種模式(蓮藕-甲魚模式、蓮藕-彩鯉模式以及蓮藕-泥鰍模式), 以單養(yǎng)甲魚模式作為對(duì)照, 于種養(yǎng)結(jié)合前(2013年3月)、種養(yǎng)結(jié)合后作物生長(zhǎng)旺盛期(2013年8月)以及魚類捕撈后(2014年1月)3個(gè)時(shí)期對(duì)各試驗(yàn)田塊底棲動(dòng)物進(jìn)行了取樣, 分析種養(yǎng)結(jié)合前后藕田底棲動(dòng)物的種類構(gòu)成、密度、生物量和多樣性的變化。結(jié)果表明, 種養(yǎng)結(jié)合模式對(duì)底棲動(dòng)物種類無(wú)顯著影響, 共采集到底棲動(dòng)物6科12屬13種。但藕田套養(yǎng)水產(chǎn)動(dòng)物, 由于水產(chǎn)動(dòng)物活動(dòng)對(duì)底泥的擾動(dòng), 底棲動(dòng)物多樣性有所下降。種養(yǎng)結(jié)合模式田塊水生昆蟲(chóng)密度、生物量以及底棲動(dòng)物總密度、總生物量均較種養(yǎng)結(jié)合前大幅度增加。3種種養(yǎng)結(jié)合模式種養(yǎng)結(jié)合后水生昆蟲(chóng)密度、生物量以及底棲動(dòng)物總密度、總生物量的平均增加幅度分別達(dá)到12倍、336倍、11倍和273倍。而單養(yǎng)甲魚模式池塘放養(yǎng)甲魚后底棲動(dòng)物生物量較放養(yǎng)前有所減少。另外, 與單養(yǎng)甲魚模式相比, 蓮藕-甲魚種養(yǎng)結(jié)合模式水生昆蟲(chóng)密度、生物量以及底棲動(dòng)物總密度、總生物量均有所提高, 而寡毛類密度、生物量則有所降低。此外, 采用Shannon-Wiener多樣性指數(shù)和BI生物指數(shù)(Hilsenhoff生物指數(shù))對(duì)3種種養(yǎng)結(jié)合模式藕田水質(zhì)進(jìn)行了評(píng)價(jià)。結(jié)果表明, 采用BI生物指數(shù)評(píng)價(jià)的結(jié)果與實(shí)際情況較為吻合, 3種種養(yǎng)結(jié)合模式中水質(zhì)狀況以蓮藕-彩鯉模式最好, 而蓮藕-泥鰍模式水質(zhì)最差。

藕-魚種養(yǎng)結(jié)合模式 底棲動(dòng)物 密度 生物量 多樣性指數(shù) 水質(zhì)

浙江北部毗鄰江蘇地區(qū)(嘉興市北部)地勢(shì)平坦, 地面高程低, 加之近年來(lái)由于不合理開(kāi)采地下水等引起的地面沉降, 內(nèi)外水位常年倒掛, 農(nóng)田長(zhǎng)期處于水淹狀態(tài), 屬典型的洼地濕地區(qū)域。長(zhǎng)期以來(lái), 這一地區(qū)傳統(tǒng)農(nóng)業(yè)主要以水稻、春花作物種植以及水產(chǎn)養(yǎng)殖為主。但種糧易澇, 而單一、大規(guī)模的水產(chǎn)養(yǎng)殖也對(duì)周邊環(huán)境帶來(lái)了一定的污染, 嚴(yán)重制約了當(dāng)?shù)剞r(nóng)業(yè)的發(fā)展[1-2]。自2009年以來(lái), 當(dāng)?shù)亻_(kāi)始探索利用低洼稻田創(chuàng)新農(nóng)作制度, 將水產(chǎn)養(yǎng)殖與水生作物種植結(jié)合起來(lái), 發(fā)展綜合種養(yǎng)模式。由于經(jīng)濟(jì)效益較為可觀, 種養(yǎng)結(jié)合模式得到了眾多農(nóng)業(yè)龍頭企業(yè)和農(nóng)民的歡迎。近年來(lái), 種養(yǎng)結(jié)合模式面積迅速擴(kuò)大。據(jù)嘉興市秀洲區(qū)農(nóng)業(yè)經(jīng)濟(jì)局統(tǒng)計(jì), 2015年僅嘉興市秀洲區(qū)全區(qū)種養(yǎng)結(jié)合模式面積已達(dá)570 hm2。

國(guó)內(nèi)外研究表明, 水產(chǎn)養(yǎng)殖與傳統(tǒng)農(nóng)業(yè)相結(jié)合的農(nóng)業(yè)-水產(chǎn)復(fù)合生態(tài)模式(integrated agri-aquaculture systems, IAAS)是促進(jìn)濕地農(nóng)業(yè)可持續(xù)發(fā)展、保證糧食安全的有效途徑[3-5]。在這一復(fù)合生態(tài)系統(tǒng)中, 水產(chǎn)養(yǎng)殖所產(chǎn)生的廢棄物等可以作為農(nóng)業(yè)生產(chǎn)的營(yíng)養(yǎng)和能量, 因而, 該模式具有較高的資源利用效率和系統(tǒng)生產(chǎn)力[6-7]。目前, 這一模式在世界上許多國(guó)家和地區(qū)都有分布, 其中尤以亞洲國(guó)家發(fā)展最為成熟, 相關(guān)科學(xué)研究也開(kāi)展得最為系統(tǒng)、深入。例如, 國(guó)際水生生物資源管理中心曾對(duì)亞洲各地區(qū)典型的濕地生態(tài)種養(yǎng)結(jié)合模式進(jìn)行了系統(tǒng)總結(jié)[8], Edwards等[9-10]對(duì)作物-牲畜-魚復(fù)合種養(yǎng)模式進(jìn)行了系統(tǒng)總結(jié)。在各種農(nóng)業(yè)-水產(chǎn)復(fù)合生態(tài)模式中, 歷史最為悠久, 應(yīng)用范圍最廣的莫過(guò)于稻田種養(yǎng)模式。國(guó)內(nèi)外針對(duì)這一模式開(kāi)展了大量的研究, 主要集中于稻田種養(yǎng)模式的生態(tài)、經(jīng)濟(jì)效益[11-16]、病蟲(chóng)草害的控制[17-20]以及對(duì)稻田生態(tài)環(huán)境的影響[21-31]等方面。近年來(lái), 不少學(xué)者針對(duì)稻田種養(yǎng)模式對(duì)稻田水生生物的影響開(kāi)展了一系列研究, 如Ali[32]對(duì)稻田養(yǎng)魚模式水體浮游甲殼動(dòng)物以及輪蟲(chóng)群落的季節(jié)動(dòng)態(tài)進(jìn)行了系統(tǒng)研究, 李巖等[33-34]對(duì)稻蟹共作模式對(duì)水體浮游生物和底棲動(dòng)物多樣性的影響進(jìn)行了系統(tǒng)研究, 曹湊貴等[35]、汪金平等[36]以及王昌付等[37]對(duì)稻田養(yǎng)鴨模式對(duì)稻田水生生物的影響進(jìn)行了系統(tǒng)研究。

近年來(lái), 隨著種植業(yè)結(jié)構(gòu)的調(diào)整優(yōu)化, 一些地區(qū)充分利用當(dāng)?shù)刈匀毁Y源優(yōu)勢(shì), 瞄準(zhǔn)國(guó)內(nèi)外市場(chǎng)需求, 把水生蔬菜作為重要的特色蔬菜品種進(jìn)行培育, 有力促進(jìn)了水生蔬菜產(chǎn)業(yè)的大力發(fā)展。目前我國(guó)水生蔬菜種植面積在73.3萬(wàn)hm2以上,主要種植種類包括蓮藕()、茭白()、芋頭()、荸薺()、慈姑()、菱()、水蕹菜()、芡實(shí)()、水芹()、莼菜()、豆瓣菜()、蔞蒿()及蒲菜()等, 總產(chǎn)值達(dá)550億元, 而蓮藕是其中栽培面積最大的作物, 全國(guó)栽培面積達(dá)40萬(wàn)hm2[38]。水生蔬菜產(chǎn)業(yè)的大力發(fā)展, 也促進(jìn)了水生蔬菜種植與水產(chǎn)養(yǎng)殖相結(jié)合的綜合種養(yǎng)模式的發(fā)展。特別是藕田養(yǎng)殖模式, 近年來(lái)面積增加顯著。但由于藕田種養(yǎng)模式技術(shù)要求較單養(yǎng)及單種模式要高, 而關(guān)于這一模式開(kāi)展的系統(tǒng)研究與稻田種養(yǎng)模式相比又明顯偏少, 這也從一方面限制了該模式的發(fā)展。目前已有的一些研究主要集中于對(duì)種養(yǎng)結(jié)合后蓮藕、魚類生長(zhǎng)狀況[2,39-40]以及對(duì)藕田水體、土壤理化性狀影響的研究[40-41]上, 而對(duì)藕田水生生物包括浮游生物以及底棲動(dòng)物等的影響的研究很少。底棲動(dòng)物是水生態(tài)系統(tǒng)的一個(gè)重要組成部分, 部分底棲動(dòng)物本身具有很高的經(jīng)濟(jì)價(jià)值, 可以作為水產(chǎn)動(dòng)物的天然餌料, 部分底棲動(dòng)物還可作為環(huán)境監(jiān)測(cè)的指示生物。本文研究了藕魚種養(yǎng)結(jié)合模式對(duì)藕田底泥中底棲動(dòng)物群落結(jié)構(gòu)及其多樣性的影響, 以期為藕田種養(yǎng)模式水體生物多樣性保護(hù)提供依據(jù), 為藕田種養(yǎng)模式的可持續(xù)發(fā)展提供參考。

1 材料與方法

1.1 試驗(yàn)地點(diǎn)與材料

試驗(yàn)地點(diǎn)在浙江省嘉興市秀洲區(qū)王江涇鎮(zhèn)浙江北部灣濕地農(nóng)業(yè)生態(tài)科技有限公司園區(qū)內(nèi)(N30°52￠322, E120°43￠462)。選取該園區(qū)內(nèi)具有代表性的3種藕-魚種養(yǎng)結(jié)合模式開(kāi)展研究, 這3種模式分別為蓮藕-甲魚模式()、蓮藕-泥鰍模式()以及蓮藕-彩鯉(elumbo )模式。另外, 考慮到浙江北部灣濕地農(nóng)業(yè)生態(tài)科技有限公司園區(qū)內(nèi), 以蓮藕-甲魚模式面積最大, 因此本研究選取單養(yǎng)甲魚池塘作為對(duì)照。種養(yǎng)結(jié)合藕田于四周挖一條深1.2 m、寬1.2 m的圍溝, 中間挖一條寬0.8 m、深0.8 m, 兩頭貫通的十字交叉型魚溝。各試驗(yàn)田塊于2013年1月初左右, 魚類捕撈完后排干池水進(jìn)行曬塘, 至2月中旬左右再全塘潑灑生石灰進(jìn)行消毒。消毒1~2周后放滿池水。于2013年3月下旬蓮藕定植前對(duì)各試驗(yàn)田塊底棲動(dòng)物進(jìn)行第一次采樣, 此時(shí)即為應(yīng)用種養(yǎng)結(jié)合模式前底棲動(dòng)物狀況, 文中統(tǒng)一定義為“種養(yǎng)結(jié)合前”時(shí)期。于4月上旬種植蓮藕, 11月底開(kāi)始采收, 種養(yǎng)結(jié)合藕田不施肥, 其他日常管理措施同當(dāng)?shù)爻Ｒ?guī)蓮藕栽培。藕田魚苗則于5月上旬投放。單養(yǎng)甲魚塘以及蓮藕-甲魚模式田塊中甲魚日常以投喂動(dòng)物性飼料為主, 投放于固定食臺(tái)上, 每日早、晚各一次; 蓮藕-彩鯉模式不投喂飼料; 而蓮藕-泥鰍模式日常主要投喂魚類內(nèi)臟及生豬宰殺后的下腳料等為主, 將魚類內(nèi)臟及下腳料煮熟后直接定點(diǎn)潑灑于藕田一角落。各試驗(yàn)田塊水產(chǎn)動(dòng)物于翌年1月份捕撈。具體各模式面積、放養(yǎng)魚苗規(guī)格以及放養(yǎng)量等見(jiàn)表1。于2013年8月中旬蓮藕及水產(chǎn)動(dòng)物生長(zhǎng)旺盛期以及2014年1月初蓮藕采收完畢且魚類捕撈完后兩個(gè)時(shí)期再次對(duì)各模式田塊底棲動(dòng)物進(jìn)行采樣。這兩個(gè)時(shí)期均為應(yīng)用種養(yǎng)結(jié)合模式后的時(shí)期, 文中統(tǒng)一定義為“種養(yǎng)結(jié)合后”時(shí)期, 兩個(gè)時(shí)期底棲動(dòng)物的平均現(xiàn)存量特征即為應(yīng)用種養(yǎng)結(jié)合模式后底棲動(dòng)物的現(xiàn)存量特征。底棲動(dòng)物的采集分為定量采集和定性采集。定量樣品用1/16 m2的彼得生采泥器采集, 每一田塊采集3次后將泥樣混合, 經(jīng)24目?cm-1的篩子篩洗后, 置于白色解剖盤中分撿動(dòng)物標(biāo)本, 并用10%的福爾馬林固定, 然后進(jìn)行種類鑒定、計(jì)數(shù)并稱重。另外, 采用彼德森采泥器結(jié)合40目手抄網(wǎng)增加圍溝和田內(nèi)隨機(jī)采樣, 以進(jìn)行底棲動(dòng)物的定性分析。底棲動(dòng)物濕重的測(cè)定方法是: 先用濾紙吸干水份, 然后在精確到0.000 1 g的電子天平上稱量(其中軟體動(dòng)物為帶殼濕重)。最后將密度和生物量數(shù)據(jù)換算成單位面積的含量。底棲動(dòng)物鑒定水平大部分到屬或種, 鑒定參考相關(guān)文獻(xiàn)[42-45]進(jìn)行。

表1 不同藕-魚種養(yǎng)結(jié)合模式田塊面積及水產(chǎn)動(dòng)物放養(yǎng)方案

1.2 多樣性指數(shù)的計(jì)算方法

采用Simpson多樣性指數(shù)和Shannon-Wiener多樣性指數(shù)對(duì)種養(yǎng)結(jié)合前后底棲動(dòng)物多樣性進(jìn)行評(píng)價(jià)。

Simpson多樣性指數(shù)計(jì)算公式:

= 1–∑(n/)2(1)

Shannon-Wiener多樣性指數(shù)計(jì)算公式:

= –∑[(n/)ln(n/)] (2)

式中:n為單位面積樣品中第種的密度(ind×m-2),為單位面積樣品中收集到的底棲動(dòng)物的總密度(ind×m-2)。

采用Shannon-Wiener指數(shù)和BI指數(shù)(Hilsenhoff生物指數(shù))對(duì)各模式藕田的水質(zhì)進(jìn)行生物評(píng)價(jià)。

Shannon-Wiener指數(shù)評(píng)價(jià)標(biāo)準(zhǔn): 指數(shù)值>3, 清潔; 2~3, 輕度污染; 1~2, 中度污染; 0~1, 嚴(yán)重污染[46]。

BI生物指數(shù)計(jì)算公式:

BI=∑t(n/) (3)

式中:n為第個(gè)分類單元(通常為屬級(jí)或種級(jí))的個(gè)體數(shù),為樣本總個(gè)體數(shù),t為第個(gè)分類單元的耐污值。底棲動(dòng)物的耐污值主要參考王備新等[47]、張躍平[48]以及秦春燕[49]的資料。

BI生物指數(shù)評(píng)價(jià)標(biāo)準(zhǔn): 指數(shù)值<3.50, 極清潔; 3.51~4.50, 很清潔; 4.51~5.50, 清潔; 5.51~6.50, 一般; 6.51~7.50, 輕度污染; 7.51~8.50, 中度污染; 8.51~ 10, 嚴(yán)重污染[50-51]。

1.3 數(shù)據(jù)分析

采用Microsoft Excel 2013進(jìn)行數(shù)據(jù)分析。

2 結(jié)果與分析

2.1 不同種養(yǎng)結(jié)合模式的底棲動(dòng)物種類變化

試驗(yàn)共采集到底棲動(dòng)物6科12屬13種(表2), 主要以寡毛類及水生昆蟲(chóng)為主。從種養(yǎng)結(jié)合前后底棲動(dòng)物種類對(duì)比上看, 除裸澤蛭()這一偶見(jiàn)種在種養(yǎng)結(jié)合后未采集到外, 其他種類種養(yǎng)結(jié)合前后各時(shí)期均有采集到。

表2 藕-魚種養(yǎng)結(jié)合模式種養(yǎng)結(jié)合前后底棲動(dòng)物種類變化

“種養(yǎng)結(jié)合前”指田塊整理完即將種植蓮藕前的時(shí)期, “種養(yǎng)結(jié)合后”指種植蓮藕及放養(yǎng)水產(chǎn)動(dòng)物后的時(shí)期。Before lotus-fish co-culture period refers to the period after the field preparation but before lotus planting. After lotus-fish co-culture period refers to the period after the lotus aquatic animals co-culture for some time.

2.2 不同種養(yǎng)結(jié)合模式的底棲動(dòng)物密度、生物量變化

從種養(yǎng)結(jié)合后各模式底棲動(dòng)物密度、生物量變化上看(圖1), 種養(yǎng)結(jié)合后底棲動(dòng)物總密度、總生物量均有所增加。3種種養(yǎng)結(jié)合模式種養(yǎng)結(jié)合后底棲動(dòng)物總密度和總生物量的平均增加幅度分別達(dá)到12倍和336倍。各類群中, 水生昆蟲(chóng)的密度和生物量增加較多, 3種種養(yǎng)結(jié)合模式種養(yǎng)結(jié)合后水生昆蟲(chóng)密度和生物量的平均增加幅度分別為11倍和273倍。另外, 各種養(yǎng)結(jié)合模式田塊所采集的定量樣品中均未檢測(cè)到軟體動(dòng)物及其他底棲動(dòng)物, 而單養(yǎng)甲魚模式池塘在放養(yǎng)甲魚前的樣品中檢測(cè)到了軟體動(dòng)物及其他底棲動(dòng)物, 但未檢測(cè)到寡毛類。且單養(yǎng)甲魚模式池塘在放養(yǎng)甲魚后, 水生昆蟲(chóng)密度、生物量均有所減少, 而底棲動(dòng)物總密度則比放養(yǎng)甲魚前有所增加, 但底棲動(dòng)物總生物量則有所減少。蓮藕-甲魚種養(yǎng)結(jié)合模式與單養(yǎng)甲魚模式相比, 在放養(yǎng)甲魚后,水生昆蟲(chóng)密度、生物量均要高, 而寡毛類密度、生物量則均要低, 但底棲動(dòng)物總密度、總生物量仍要高于單養(yǎng)模式。

2.3 不同種養(yǎng)結(jié)合模式的底棲動(dòng)物生物多樣性指數(shù)變化

種養(yǎng)結(jié)合后底棲動(dòng)物生物多樣性指數(shù)的變化如圖2所示。種養(yǎng)結(jié)合后, Shannon-Wiener指數(shù)、Simpson指數(shù)均有所下降, 表明藕田套養(yǎng)魚類后, 底棲動(dòng)物多樣性有所下降。

2.4 不同種養(yǎng)結(jié)合模式的水質(zhì)生物學(xué)評(píng)價(jià)

由表3可見(jiàn), 根據(jù)Shannon-Wiener指數(shù)評(píng)價(jià)污染狀況標(biāo)準(zhǔn), 蓮藕-甲魚、蓮藕-泥鰍以及蓮藕-彩鯉3種模式種養(yǎng)結(jié)合后, Shannon-Wiener指數(shù)雖均較種養(yǎng)結(jié)合前有所降低, 表明水質(zhì)變差, 但水質(zhì)級(jí)別未有變化, 均呈嚴(yán)重污染狀態(tài)。種養(yǎng)結(jié)合后3種模式中以蓮藕-泥鰍模式Shannon-Wiener指數(shù)值最高, 而蓮藕-彩鯉模式Shannon-Wiener指數(shù)值最低。僅從Shannon-Wiener指數(shù)值來(lái)看, 3種種養(yǎng)結(jié)合模式中水質(zhì)狀況以蓮藕-泥鰍模式最好, 而蓮藕-彩鯉模式水質(zhì)最差。

表3 不同藕-魚種養(yǎng)結(jié)合模式種養(yǎng)結(jié)合前后生物指數(shù)值和水質(zhì)評(píng)價(jià)結(jié)果

BI生物指數(shù)方面, 蓮藕-甲魚模式, 種養(yǎng)結(jié)合后BI生物指數(shù)值較種養(yǎng)結(jié)合前明顯升高, 表明水質(zhì)明顯變差, 水質(zhì)級(jí)別下降兩個(gè)等級(jí), 由一般狀態(tài)轉(zhuǎn)變?yōu)橹卸任廴緺顟B(tài)。而蓮藕-泥鰍以及蓮藕-彩鯉模式, 種養(yǎng)結(jié)合后, BI生物指數(shù)雖較種養(yǎng)結(jié)合前有所升高(表明水質(zhì)有所變差), 但水質(zhì)級(jí)別未有變化。從BI生物指數(shù)值來(lái)看, 種養(yǎng)結(jié)合后3種模式中以蓮藕-泥鰍模式BI指數(shù)值最高, 而蓮藕-彩鯉模式BI生物指數(shù)值最低。根據(jù)BI生物指數(shù)評(píng)價(jià)的結(jié)果表明, 3種種養(yǎng)結(jié)合模式中水質(zhì)狀況以蓮藕-彩鯉模式相對(duì)最好,而蓮藕-泥鰍模式水質(zhì)相對(duì)最差。根據(jù)程旺大等[52]采用化學(xué)方法對(duì)這3種種養(yǎng)結(jié)合模式水質(zhì)評(píng)價(jià)的研究, 整體水質(zhì)以蓮藕-彩鯉模式相對(duì)最好, 而蓮藕-泥鰍模式水質(zhì)相對(duì)最差。故本研究中采用BI生物指數(shù)評(píng)價(jià)的結(jié)果與實(shí)際情況較為吻合。

3 結(jié)論與討論

低洼田藕-魚種養(yǎng)結(jié)合模式作為一種新型的濕地循環(huán)農(nóng)業(yè)模式, 具有較高的經(jīng)濟(jì)、社會(huì)和生態(tài)效益。但目前有關(guān)這種模式水生生物群落結(jié)構(gòu)、多樣性方面的研究較少, 特別是底棲動(dòng)物方面。

本研究表明, 種養(yǎng)結(jié)合模式對(duì)底棲動(dòng)物種類無(wú)顯著影響, 但藕田套養(yǎng)水產(chǎn)動(dòng)物后, 由于水產(chǎn)動(dòng)物活動(dòng)以及覓食等對(duì)底泥的擾動(dòng), 底棲動(dòng)物多樣性有所下降。這與李巖等[33-34]針對(duì)稻蟹共作模式以及曹湊貴等[35]、王昌付等[37]針對(duì)稻鴨共作模式開(kāi)展的對(duì)底棲動(dòng)物的影響的研究相一致。

根據(jù)已有一些對(duì)養(yǎng)魚池塘底棲動(dòng)物群落時(shí)空變化的研究[53-55], 養(yǎng)魚池塘底棲動(dòng)物生物量的峰值多出現(xiàn)在春季, 而后緩慢下降, 至秋季可能再次迎來(lái)一小高峰, 然后再次下降。也就是說(shuō), 養(yǎng)魚池塘底棲動(dòng)物春、秋兩季生物量是相對(duì)較高的, 而夏、冬兩季生物量較低。從本研究對(duì)單養(yǎng)甲魚模式的研究來(lái)看, 雖然秋季未對(duì)該模式池塘底棲動(dòng)物進(jìn)行調(diào)查, 但從放養(yǎng)甲魚前(春季)以及放養(yǎng)甲魚后(夏季、冬季兩次平均值)底棲動(dòng)物生物量特征推斷, 池塘單養(yǎng)甲魚模式底棲動(dòng)物時(shí)空變化可能也遵循這一趨勢(shì)。但若采用種養(yǎng)結(jié)合模式, 底棲動(dòng)物的變化趨勢(shì)則就有所不同。從本研究中蓮藕-甲魚式種養(yǎng)結(jié)合后底棲動(dòng)物變化上看, 種養(yǎng)結(jié)合后(夏季、冬季兩次平均值)水生昆蟲(chóng)密度、生物量以及底棲動(dòng)物總密度、總生物量均較種養(yǎng)結(jié)合前(春季)有大幅增加。蓮藕-泥鰍和蓮藕-彩鯉這兩種模式種養(yǎng)結(jié)合后底棲動(dòng)物現(xiàn)存量變化的趨勢(shì)亦是如此。此外, 與單養(yǎng)甲魚模式相比, 同樣在放養(yǎng)甲魚后, 蓮藕-甲魚種養(yǎng)結(jié)合模式水生昆蟲(chóng)密度、生物量以及底棲動(dòng)物總密度、總生物量均要高于單養(yǎng)模式, 而寡毛類密度、生物量則要低于單養(yǎng)模式。分析其原因可能是種養(yǎng)結(jié)合條件下, 蓮藕的存在大大降低了水產(chǎn)動(dòng)物活動(dòng)對(duì)底泥擾動(dòng)的影響, 從而為底棲動(dòng)物提供了更為穩(wěn)定的生境條件, 故底棲動(dòng)物數(shù)量在夏季以及冬季數(shù)量并未下降。而另外一方面, 蓮藕-甲魚種養(yǎng)結(jié)合模式與單養(yǎng)甲魚模式相比, 由于蓮藕的吸收作用, 水體以及底泥營(yíng)養(yǎng)水平要比單養(yǎng)池塘低, 因此耐污的顫蚓科寡毛類數(shù)量要少。

目前, 采用生物監(jiān)測(cè)法監(jiān)測(cè)湖泊、河流水質(zhì)的研究較多, 而鮮見(jiàn)采用生物評(píng)價(jià)法評(píng)價(jià)池塘水質(zhì)的研究。本研究采用兩種生物指數(shù)對(duì)不同種養(yǎng)結(jié)合模式種養(yǎng)結(jié)合后藕田水質(zhì)進(jìn)行了評(píng)價(jià), 對(duì)照作者同期采用化學(xué)方法開(kāi)展的水質(zhì)評(píng)價(jià)研究, 確認(rèn)BI生物指數(shù)適合作為藕-魚種養(yǎng)結(jié)合模式底棲動(dòng)物水質(zhì)生物評(píng)價(jià)的指標(biāo), 運(yùn)用該指數(shù)評(píng)價(jià)的結(jié)果與實(shí)際情況較為吻合。根據(jù)評(píng)價(jià)結(jié)果, 3種種養(yǎng)結(jié)合模式中, 整體水質(zhì)以蓮藕-彩鯉模式相對(duì)最好, 而蓮藕-泥鰍模式水質(zhì)相對(duì)最差。從實(shí)際情況看, 6—9月份, 由于投飼等原因, 蓮藕-甲魚以及蓮藕-泥鰍兩種模式藕田水體富營(yíng)養(yǎng)化嚴(yán)重, 水華爆發(fā), 而蓮藕-彩鯉模式藕田未見(jiàn)水華爆發(fā)。

藕魚共生生態(tài)系統(tǒng)是一個(gè)隨著魚類的生長(zhǎng)發(fā)育而變化的動(dòng)態(tài)系統(tǒng)。本文在研究底棲動(dòng)物時(shí), 僅在蓮藕、魚類生長(zhǎng)旺盛時(shí)期以及魚類捕撈收獲后兩次進(jìn)行取樣, 并沒(méi)有充分研究種養(yǎng)結(jié)合系統(tǒng)中魚類的動(dòng)態(tài)變化。結(jié)合共生環(huán)境、其他水生動(dòng)植物、蓮藕生長(zhǎng)及魚類習(xí)性, 系統(tǒng)地了解該共生模式下的生態(tài)系統(tǒng)組份動(dòng)態(tài)變化, 將為濕地農(nóng)業(yè)種養(yǎng)結(jié)合模式提供更為系統(tǒng)的理論指導(dǎo)。

致謝 在本研究過(guò)程中, 嘉興市農(nóng)業(yè)技術(shù)推廣基金會(huì)蔣唯民會(huì)長(zhǎng)、杜云昌原會(huì)長(zhǎng)、楊治明副會(huì)長(zhǎng)、高寅華秘書長(zhǎng)、顧忠烈副秘書長(zhǎng)和嘉興市秀洲區(qū)農(nóng)業(yè)技術(shù)推廣基金會(huì)周志明會(huì)長(zhǎng)等給予了大力幫助和支持, 在此表示感謝。

References

[1] 周萍. 秀洲區(qū)北部發(fā)展水生蔬菜的優(yōu)勢(shì)與措施[J]. 浙江農(nóng)業(yè)科學(xué), 2010(3): 466–468 Zhou P. The advantage and measures for developing the aquatic vegetable planting in the north of Xiuzhou District[J]. Journal of Zhejiang Agricultural Sciences, 2010(3): 466–468

[2] 姚祥坦, 沈亞強(qiáng), 張紅梅, 等. 低洼田濕地“植?魚”種養(yǎng)結(jié)合模式對(duì)蓮藕、菱生長(zhǎng)發(fā)育及品質(zhì)的影響[J]. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào), 2012, 20(12): 1643–1649 Yao X T, Shen Y Q, Zhang H M, et al. Effects of “plant-fish” integrated farming system on the growth and quality ofGaertn andNakano in the lowland areas[J]. Chinese Journal of Eco-Agriculture, 2012, 20(12): 1643–1649

[3] Cassman K G, Wood S, Sze Choo P, et al. Cultivated systems[M]//Hassan R, Scholes R, Ash N. Ecosystems and Human Well-Being: Current State and Trends, Volume 1. Washington: Island Press, 2005: 745–794

[4] Pretty J. Agricultural sustainability: Concepts, principles and evidence[J]. Philosophical Transactions of the Royal Society B: Biological Sciences, 2008, 363(1491): 447–465

[5] Kumaresan A, Pathak K A, Bujarbaruah K M, et al. Analysis of integrated animal-fish production system under subtropical hill agro ecosystem in India: Growth performance of animals, total biomass production and monetary benefit[J]. Tropical Animal Health and Production, 2009, 41(3): 385–391

[6] Berg H. Rice monoculture and integrated rice-fish farming in the Mekong Delta, Vietnam — Economic and ecological considerations[J]. Ecological Economics, 2002, 41(1): 95–107

[7] Pant J, Demaine H, Edwards P. Bio-resource flow in integrated agriculture-aquaculture systems in a tropical monsoonal climate: A case study in Northeast Thailand[J]. Agricultural Systems, 2005, 83(2): 203–219

[8] Pullin R S V, Shehadeh Z H. Integrated agriculture- aquaculture farming systems[C]//Proceedings of the ICLARM- SEARCA Conference on Integrated Agriculture-Aquaculture Farming Systems. Manila: International Center for Living Aquatic Resources Management (ICLARM), 1979: 1–258

[9] Edwards P, Pullin R S V, Gartner J A. Research and Education for the Development of Integrated Crop-Livestock-Fish Farming Systems in the Tropics[M]. Manila: International Center for Living Aquatic Resources Management (ICLARM), 1988: 1–53

[10] Edwards P. Environmental issues in integrated agriculture- aquaculture and wastewater-fed fish culture systems[C]// Pullin R S V, Rosenthal H, Maclean J L. Environment and Aquaculture in Developing Countries. Manila: International Center for Living Aquatic Resources Management (ICLARM), Deutsche Gesellschatt für Technische Zusammenarbeit (GTZ) GmbH, 1993: 139–170

[11] 倪達(dá)書, 汪建國(guó). 論稻魚共生生態(tài)系統(tǒng)的應(yīng)用價(jià)值[J]. 水產(chǎn)科技情報(bào), 1983(6): 1–4 Ni D S, Wang J G. Application value of integrated rice-fish system[J]. Fisheries Sicence & Technology Information, 1983(6): 1–4

[12] 盧升高, 黃沖平. 稻田養(yǎng)魚生態(tài)經(jīng)濟(jì)效益的初步分析[J]. 生態(tài)學(xué)雜志, 1988(4): 26–29 Lu S G, Huang C P. Economic and ecological effects of fish culture in paddy fields[J]. Chinese Journal of Ecology, 1988(4): 26–29

[13] 王纓, 雷慰慈. 稻田種養(yǎng)模式生態(tài)效益研究[J]. 生態(tài)學(xué)報(bào), 2000, 20(2): 311–316 Wang Y, Lei W C. Studies on the ecological effect of planting breeding models in the rice field[J]. Acta Ecologica Sinica, 2000, 20(2): 311–316

[14] 王華, 黃璜. 濕地稻田養(yǎng)魚、鴨復(fù)合生態(tài)系統(tǒng)生態(tài)經(jīng)濟(jì)效益分析[J]. 中國(guó)農(nóng)學(xué)通報(bào), 2002, 18(1): 71–75 Wang H, Huang H. Analysis on ecological and economic benefits of complex ecosystem in wetland paddy fields[J]. Chinese Agricultural Science Bulletin, 2002, 18(1): 71–75

[15] 蔣艷萍, 章家恩, 朱可峰. 稻田養(yǎng)魚的生態(tài)效應(yīng)研究進(jìn)展[J]. 仲愷農(nóng)業(yè)技術(shù)學(xué)院學(xué)報(bào), 2007, 20(4): 71–75 Jiang Y P, Zhang J E, Zhu K F. Reviews on ecological effects of rice-fish farming system[J]. Journal of Zhongkai University of Agriculture and Technology, 2007, 20(4): 71–75

[16] 林孝麗, 周應(yīng)恒. 稻田種養(yǎng)結(jié)合循環(huán)農(nóng)業(yè)模式生態(tài)環(huán)境效應(yīng)實(shí)證分析——以南方稻區(qū)稻-魚模式為例[J]. 中國(guó)人口·資源與環(huán)境, 2012, 22(3): 37–42 Lin X L, Zhou Y H. An analysis on the eco-environment effect of circular agriculture mode of planting-culture in the paddy field[J]. China Population Resources and Environment, 2012, 22(3): 37–42

[17] Rothuis A J, Vromant N, Xuan V T, et al. The effect of rice seeding rate on rice and fish production, and weed abundance in direct-seeded rice-fish culture[J]. Aquaculture, 1999, 172(3/4): 255–274

[18] Vromant N, Nhan D K, Chau N T H, et al. Effect of stocked fish on rice leaf folderand rice casewormpopulations in intensive rice culture[J]. Biocontrol Science and Technology, 2003, 13(3): 285–297

[19] Xie J, Hu L L, Tang J J, et al. Ecological mechanisms underlying the sustainability of the agricultural heritage rice-fish coculture system[J]. Proceedings of the National Academy of Sciences of the United States of America, 2011, 108(50): E1381–E1387

[20] 呂東鋒, 王武, 馬旭洲, 等. 稻蟹共生對(duì)稻田雜草的生態(tài)防控試驗(yàn)研究[J]. 湖北農(nóng)業(yè)科學(xué), 2011, 50(8): 1574–1578 Lü D F, Wang W, Ma X Z, et al. Ecological prevention and control of weeds in rice-crab polycultured field[J]. Hubei Agricultural Sciences, 2011, 50(8): 1574–1578

[21] Oehme M, Frei M, Razzak M A, et al. Studies on nitrogen cycling under different nitrogen inputs in integrated rice-fish culture in Bangladesh[J]. Nutrient Cycling in Agroecosvstems, 2007, 79(2): 181–191

[22] Frei M, Razzak M A, Hossain M M, et al. Methane emissions and related physicochemical soil and water parameters in rice-fish systems in Bangladesh[J]. Agriculture, Ecosystems & Environment, 2007, 120(2/4): 391–398

[23] Frei M, Becker K. Integrated rice-fish culture: Coupled production saves resources[J]. Natural Resources Forum, 2005, 29(2): 135–143

[24] 黃毅斌, 翁伯琦, 唐建陽(yáng), 等. 稻-萍-魚體系對(duì)稻田土壤環(huán)境的影響[J]. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào), 2001, 9(1): 74–76 Huang Y B, Weng B Q, Tang J Y, et al. Effect of rice- azolla-fish system on soil environment of rice field[J]. Chinese Journal of Eco-Agriculture, 2001, 9(1): 74–76

[25] 劉元生, 孟慶紅, 何騰兵, 等. 稻田生態(tài)養(yǎng)魚水質(zhì)動(dòng)態(tài)與水稻生長(zhǎng)及經(jīng)濟(jì)效益研究[J]. 耕作與栽培, 2003, (5): 5–6 Liu Y S, Meng Q H, He T B, et al. Studies in the water quality dynamics, rice growth and economic benefits of fish culture in paddy fields[J]. Tillage and Cultivation, 2003, (5): 5–6

[26] 高洪生. 北方寒地稻田養(yǎng)魚對(duì)農(nóng)田生態(tài)環(huán)境的影響初報(bào)[J]. 中國(guó)農(nóng)學(xué)通報(bào), 2006, 22(7): 470–472 Gao H S. Preliminary report of the influence of the rice field fish culture to the farmland ecology environment in north cold area[J]. Chinese Agricultural Science Bulletin, 2006, 22(7): 470–472

[27] 全國(guó)明, 章家恩, 陳瑞, 等. 稻鴨共作對(duì)稻田水體環(huán)境的影響[J]. 應(yīng)用生態(tài)學(xué)報(bào), 2008, 19(9): 2023–2028 Quan G M, Zhang J E, Chen R, et al. Effects of rice-duck farming on paddy field water environment[J]. Chinese Journal of Applied Ecology, 2008, 19(9): 2023–2028

[28] Datta A, Nayak D R, Sinhababu D P, et al. Methane and nitrous oxide emissions from an integrated rainfed rice-fish farming system of Eastern India[J]. Agriculture, Ecosystems & Environment, 2009, 129(1/3): 228–237

[29] 王昂, 王武, 馬旭洲, 等. 養(yǎng)蟹稻田水環(huán)境部分因子變化研究[J]. 湖北農(nóng)業(yè)科學(xué), 2011, 50(17): 3514–3519 Wang A, Wang W, Ma X Z, et al. Study on the changes of water environmental factors in rice-crab culture system[J]. Hubei Agricultural Sciences, 2011, 50(17): 3514–3519

[30] 汪清, 王武, 馬旭洲, 等. 稻蟹共作對(duì)土壤理化性質(zhì)的影響[J].湖北農(nóng)業(yè)科學(xué), 2011, 50(19): 3948–3952 Wang Q, Wang W, Ma X Z, et al. The effects of integrated rice-crab production on soil physical and chemical properties[J]. Hubei Agricultural Sciences, 2011, 50(19): 3948–3952

[31] Tsuruta T, Yamaguchi M, Abe S I, et al. Effect of fish in rice-fish culture on the rice yield[J]. Fisheries Science, 2011, 77(1): 95–106

[32] Ali A B. Seasonal dynamics of microcrustacean and rotifer communities in Malaysian rice fields used for rice-fish farming[J]. Hydrobiologia, 1990, 206(2): 139–148

[33] 李巖, 王武, 馬旭洲, 等. 稻蟹共作對(duì)稻田水體底棲動(dòng)物多樣性的影響[J]. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào), 2013, 21(7): 838–843 Li Y, Wang W, Ma X Z, et al. Effect of rice-crab culture system on zoobenthos diversity in paddy field[J]. Chinese Journal of Eco-Agriculture, 2013, 21(7): 838–843

[34] 李巖. 稻蟹共生對(duì)稻田水體浮游生物和底棲動(dòng)物影響的研究[D]. 上海: 上海海洋大學(xué), 2013: 1–41 Li Y. Study on the effects of plankton and zoobenthos in rice-crab culture system[D]. Shanghai: Shanghai Ocean University, 2013: 1–41

[35] 曹湊貴, 汪金平, 鄧環(huán). 稻鴨共生對(duì)稻田水生動(dòng)物群落的影響[J]. 生態(tài)學(xué)報(bào), 2005, 25(10): 2644–2648 Cao C G, Wang J P, Deng H. The impact of rice-duck intergrowth on aquatic animals community of rice fields[J]. Acta Ecologica Sinica, 2005, 25(10): 2644–2648

[36] 汪金平, 曹湊貴, 金暉, 等. 稻鴨共生對(duì)稻田水生生物群落的影響[J]. 中國(guó)農(nóng)業(yè)科學(xué), 2006, 39(10): 2001–2008 Wang J P, Cao C G, Jin H, et al. Effects of rice-duck farming on aquatic community in rice fields[J]. Scientia Agricultura Sinica, 2006, 39(10): 2001–2008

[37] 王昌付, 汪金平, 曹湊貴. 稻鴨共作對(duì)稻田水體底棲動(dòng)物生物多樣性的影響[J]. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào), 2008, 16(4): 933–937 Wang C F, Wang J P, Cao C G. Effect of rice-duck farming ecosystem on zoobenthos biodiversity in paddy field[J]. Chinese Journal of Eco-Agriculture, 2008, 16(4): 933–937

[38] 柯衛(wèi)東, 黃新芳, 李建洪, 等. 我國(guó)水生蔬菜科研與生產(chǎn)發(fā)展概況[J]. 長(zhǎng)江蔬菜, 2015(14): 33–37 Ke W D, Huang X F, Li J H, et al. Overview of aquatic vegetable production and research in China[J]. Journal of Changjiang Vegetables, 2015(14): 33–37

[39] 姚祥坦, 沈亞強(qiáng), 倪龍鳳, 等. 蓮藕-魚類種養(yǎng)結(jié)合栽培下不同蓮藕品種比較[J]. 長(zhǎng)江蔬菜, 2015(22): 61–64 Yao X T, Shen Y Q, Ni L F, et al. Comparison among different varieties of lotus root in integrated lotus root-fish farming system[J]. Journal of Changjiang Vegetables, 2015(22): 61–64

[40] Yang Y, Lin C K, Diana J S. Recycling pond mud nutrients in integrated lotus-fish culture[J]. Aquaculture, 2002, 212(1/4): 213–226

[41] 沈亞強(qiáng), 姚祥坦, 張紅梅, 等. 浙江北部低洼田濕地農(nóng)業(yè)種養(yǎng)結(jié)合模式的環(huán)境效應(yīng)[J]. 長(zhǎng)江流域資源與環(huán)境, 2014, 23(3): 351–357 Shen Y Q, Yao X T, Zhang H M, et al. Environmental effects of integrated crop-fish farming systems for low-lying wetland in the north of Zhejiang Province[J]. Resources and Environment in the Yangtze Basin, 2014, 23(3): 351–357

[42] 劉月英, 張文珍, 王躍先, 等. 中國(guó)經(jīng)濟(jì)動(dòng)物志淡水軟體動(dòng)物[M]. 北京: 科學(xué)出版社, 1979: 1–134 Liu Y Y, Zhang W Z, Wang Y X, et al. Economic Fauna of China, Freshwater Molluscs[M]. Beijing: Science Press, 1979: 1–134

[43] Brinkhurst R O. Guide to the Freshwater Aquatic Microdrile Oligochaetes of North America. Canadian Special Publication of Fisheries and Aquatic Sciences[M]. Ottawa: NRC Research Press, 1986: 1–259

[44] Morse J C, Yang L F, Tian L X. Aquatic Insects of China Useful for Monitoring Water Quality[M]. Nanjing: Hohai University Press, 1994: 1–570

[45] 王洪鑄. 中國(guó)小蚓類研究: 附中國(guó)南極長(zhǎng)城站附近地區(qū)兩新種[M]. 北京: 高等教育出版社, 2002: 1–228 Wang H Z. Studies on Taxonomy, Distribution and Ecology of Microdrile Oligochaetes of China, with Descriptions of Two New Species From the Vicinity of the Great Wall Station of China, Antarctica[M]. Beijing: Higher Education Press, 2002: 1–228

[46] 吳東浩, 王備新, 張?jiān)? 等. 底棲動(dòng)物生物指數(shù)水質(zhì)評(píng)價(jià)進(jìn)展及在中國(guó)的應(yīng)用前景[J]. 南京農(nóng)業(yè)大學(xué)學(xué)報(bào), 2011, 34(2): 129–134 Wu D H, Wang B X, Zhang Y, et al. Advances in the use of biotic index for water quality bioassessment with benthic macroinvertebrate and its perspective in China[J]. Journal of Nanjing Agricultural University, 2011, 34(2): 129–134

[47] 王備新, 楊蓮芳. 我國(guó)東部底棲無(wú)脊椎動(dòng)物主要分類單元耐污值[J]. 生態(tài)學(xué)報(bào), 2004, 24(12): 2768–2775 Wang B X, Yang L F. A study on tolerance values of benthic macroinvertebrate taxa in eastern China[J]. Acta Ecologica Sinica, 2004, 24(12): 2768–2775

[48] 張躍平. 江蘇大型底棲無(wú)脊椎動(dòng)物耐污值、BI指數(shù)及水質(zhì)生物評(píng)價(jià)研究[D]. 南京: 南京農(nóng)業(yè)大學(xué), 2006: 16–18Zhang Y P. A study on tolerance value of benthic macroinvertebrates and biotic index in Jiangsu Province[D]. Nanjing: Nanjing Agricultural University, 2006: 16–18

[49] 秦春燕. 長(zhǎng)江三角洲淡水底棲動(dòng)物耐污值修訂和BI指數(shù)水質(zhì)評(píng)價(jià)分級(jí)研究[D]. 南京: 南京農(nóng)業(yè)大學(xué), 2013: 27–34 Qin C Y. Quantitative tolerance values for common stream benthic macroinvertebrate and water quality classification use of biotic index (BI) in Yangtze River Delta[D]. Nanjing: Nanjing Agricultural University, 2013: 27–34

[50] Hilsenhoff W L. An improved biotic index of organic stream pollution[J]. Great Lakes Entomologist, 1987, 20(1): 31–39

[51] 胡成龍, 姜加虎, 陳宇煒, 等. 湖北省湖泊大型底棲動(dòng)物群落結(jié)構(gòu)及水質(zhì)生物學(xué)評(píng)價(jià)[J]. 生態(tài)環(huán)境學(xué)報(bào), 2014, 23(1): 129–138 Hu C L, Jiang J H, Chen Y W, et al. Macrozoobenthic community structure and bioassessment of water quality of shallow lakes in Hubei Province[J]. Ecology and Environmental Sciences, 2014, 23(1): 129–138

[52] 程旺大, 沈亞強(qiáng), 姚祥坦. 嘉興北部低洼田濕地農(nóng)業(yè)種養(yǎng)結(jié)合模式構(gòu)建及其機(jī)理研究(摘要)[M]//嘉興市農(nóng)業(yè)技術(shù)推廣基金會(huì). 生態(tài)循環(huán)時(shí)空換土地模式構(gòu)建與技術(shù). 上海: 上海科學(xué)技術(shù)出版社, 2014: 179–243 Cheng W D, Shen Y Q, Yao X T. Studies on the building and mechanisms of integrated crop-fish farming systems for low-lying wetland in the north of Jiaxing City (Abstract)[M]// Jiaxing Agrotechnology Extension Foundation. The Building and Mechanisms of Circular Agriculture Mode. Shanghai: Shanghai Science and Technology Press, 2014: 179–243

[53] Oertli B. Spatial and temporal distribution of the zoobenthos community in a woodland pond (Switzerland)[J]. Hydrobiologia, 1995, 300–301(1): 195–204

[54] 趙文, 董雙林, 張美昭, 等. 鹽堿池塘底棲動(dòng)物的初步研究[J]. 應(yīng)用與環(huán)境生物學(xué)報(bào), 2001, 7(3): 239–243Zhao W, Dong S L, Zhang M Z, et al. Study of macrozoobenthos in saline-alkaline pondsz[J]. Chinese Journal of Applied & Environmental Biology, 2001, 7(3): 239–243

[55] 趙峰. 池塘大型底棲動(dòng)物群落結(jié)構(gòu)及其部分生態(tài)功能的研究[D]. 武漢: 華中農(nóng)業(yè)大學(xué), 2014: 21–22 Zhao F. Studies on the community structure and some ecological function of macrozoobenthos in pond[D]. Wuhan: Huazhong Agricultural University, 2014: 21–22

Effects of integrated lotus-fish farming systems on macrozoobenthos in lotus field*

SHEN Yaqiang, YAO Xiangtan, CHENG Wangda**

(Jiaxing Academy of Agricultural Sciences, Zhejiang Province, Jiaxing 314016, China)

Integrated Agri-Aquaculture Systems (IAAS) such as rice-fish farming have been practiced for centuries in China. In these systems, on-farm wastes and by-products are recycled in relatively closed nutrient cycles. IAAS also utilizes resource efficiently and provides additional food and income to local farmers. Thus these systems are more sustainable compared with other food production systems such as monoculture systems. In the north of Jiaxing City, Zhejiang Province, a wide area of low-lying wetlands exists because of land subsidence. The permanently flooded field is not suitable for grain and oilseed rape production and thus agricultural economy development in the area is seriously restricted. As an innovation of IAAS, the trapa-fish (e.g. trapa-loach, trapa-Chinese snakehead fish and trapa-Chinese soft-shelled turtle), lotus-fish (e.g. lotus-loach, lotus-Chinese soft-shelled turtle and lotus-Chinese snakehead fish) and water bamboo-fish (e.g. water bamboo-loach) integrated patterns were being gradually developed in recent years. As an important ecological group in freshwater ecosystems, macrozoobenthos are important in material cycling and energy flow, and are widely used in environmental monitoring. In order to determine the response of macrozoobenthos diversity to lotus-fish farming, field experiments were conducted in Zhejiang Northbay Wetland Eco-agricultural Science and Technology Ltd. Co. Three typical integrated lotus-fish farming systems (including integrated lotus-soft-shelled turtle system, integrated lotus-Oujiang color common carp system and integrated lotus-loach system) along with one monoculture system (soft-shelled turtle monoculture system) were selected in the study. Ecological surveys of each system were carried out at three periods — before lotus-fish co-culture period (late March 2013), after lotus-fish co-culture and the lotus in vigorous growth period (mid-August 2013) and after fish harvesting period (early January 2014). The species composition, standing crops and diversity of samples were analyzed. Altogether, 13 macrozoobenthos taxa belonging to 6 families and 12 genera were identified from all the qualitative and quantitative samples. Results showed that there was no significant difference in the macrozoobenthos species after the adoption of integrated lotus-fish farming system. However, macrozoobenthos biodiversity decreased because of sediment disturbance caused by aquatic animals after fish stocking. The density and biomass of aquatic insects and macrozoobenthos in the integrated lotus-fish farming systems all increased after fish stocking. The average density and biomass of aquatic insects, total density and biomass of macrozoobenthos increased by 12 times and 336 times, 11 times and 273 times, respectively. However, in the soft-shelled turtle monoculture system, macrozoobenthos biomass decreased after soft-shelled turtle stocking. Meanwhile, the integrated lotus-soft-shelled turtle system had higher density and biomass of aquatic insects and macrozoobenthos compared with soft-shelled turtle monoculture system. Conversely, the density and biomass of oligochaetes in integrated lotus-soft- shelled turtle system were lower than those in monoculture system. Results of bioassessment using Hilsenhoff biotic index indicated that water quality under lotus-Oujiang color common carp system was better than that under lotus-loach system and lotus-soft-shelled turtle system.

Integrated lotus-fish farming systems; Macrozoobenthos; Density; Biomass; Diversity index; Water quality

10.13930/j.cnki.cjea.160422

Q178.1

A

1671-3990(2016)12-1598-09

2016-05-07 接受日期: 2016-08-08

*浙江省農(nóng)業(yè)技術(shù)推廣基金會(huì)2011年“創(chuàng)新農(nóng)作制度深化研究”專項(xiàng)重點(diǎn)項(xiàng)目、浙江省嘉興市科技計(jì)劃項(xiàng)目(2012AZ2019)和浙江省公益性技術(shù)應(yīng)用研究計(jì)劃項(xiàng)目(2013C32029)資助

**通訊作者:程旺大, 主要研究方向?yàn)檗r(nóng)產(chǎn)品產(chǎn)地生態(tài)環(huán)境與質(zhì)量安全。E-mail: chwd228@163.com 沈亞強(qiáng), 主要研究方向?yàn)闈竦剞r(nóng)業(yè)。E-mail: shenyaqiang@163.com

* This study was supported by the Special Fund for Farming Systems Innovation of Zhejiang Agricultural Technology Extension Foundation in 2011, the Natural Science Foundation of Jiaxing City (2012AZ2019) and the Public Welfare Technology Applied Research Projects of Zhejiang Province (2013C32029).

** Corresponding author, E-mail: chwd228@163.com

Received May 7, 2016; accepted Aug. 8, 2016